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• With initializing a member of a structure using an expression containing the sizeof operator

1. Products and Versions Concerned
   (1) The C compiler package for the R32C series V.1.01 Release 00
   (2) The C compiler package for the M32C series, M3T-NC308WA (NOTE 1)
         V.5.10 Release 1 through V.5.41 Release 01
   (3) The C compiler package for the M16C series, M3T-NC30WA (NOTE 2)
         V.5.10 Release 1 through V.5.44 Release 00

   NOTES:
    1. The M32C series is the generic name of the M32C/80 and M16C/80 
       series.
    2. The M16C series is the generic name of the M16C/60, /30, /20, /10, 
       /Tiny, and R8C/Tiny series.

2. Description
   If you initialize a member of a structure using an expression containing 
   the sizeof operator, the compiler's system error or Windows' error 
   may arise.

2.1 Conditions
    This problem occurs if the following conditions are all satisfied:
    (1) Compile options -Oconst(-OC) and -O3(-O) are selected, or any one 
        of the options -O4, -O5, -OR_MAX, and -OS_MAX is selected.
    (2) A const-qualified structure is defined outside of a function.
    (3) A member of the structure in (2) is initialized using 
        an expression containing the sizeof operator.
    (4) The member of the structure in (2) is at the top of the structure.
    (5) An expression references the member of the structure in (2) 
        using the dot (.) operator.

2.2 Example
    ------------------------------------------------------------------------
       struct S{
              int  m;                       /* Condition (4) */
       };

       const struct S t = {2+sizeof(int)};  /* Conditions (2) and (3) */

       int  n;

       void     func(void)
       {
              n = t.m;                      /* Condition (5) */
       }
    ------------------------------------------------------------------------

3. Workaround
   Initialize the member of the structure involved using a constant.
    ------------------------------------------------------------------------
       struct S{
              int  m;
       };

       const struct S t = {4};  /* Initialized using a constant */

       int  n;

       void     func(void)
       {
              n = t.m;
       }
    ------------------------------------------------------------------------

4. Schedule of Fixing the Problem
   We plan to fix this problem in the next release of the products.